In recent years, thermometers have been used in connection with medical monitors. For example, in 1994 a BCI ear thermometer was introduced by BioChem International using RS-232 to communicate with a monitor. Similarly, in 1996 DATASCOPE™ introduced an infrared ear thermometer having an infrared LED for the wireless transmission of the acquired temperature reading to the patient monitor. This thermometer was designed for use as a stand alone temperature measuring device or to be used with medical monitors via an serial or asynchronous serial connection. In 1996, the temporal artery thermometer was introduced in the form of the LTXA. The LTXA is an infrared temporal artery thermometer using an RS-232 cable data link for data transmission. The Temporal Artery thermometer may also be used with medical monitors.
For example, FIG. 2 shows a way of collecting and transmitting temperature data that includes a body portion 205, a temperature detector 210, a communications path 215, and a medical device 220. In one embodiment, a cradle 225 may be used to store the temperature detector 210. In use, the temperature detector 210 obtains a temperature reading from a body portion 205 and sends the temperature reading to the medical device 220 for display. In particular embodiments, the temperature detector 210 uses an RS-232 output and transmits the temperature reading to the medical device 220.
In this example embodiment, the temperature detector 210 obtains body temperature data from the body portion 205. With the body temperature data, an internal core temperature can be computed using an arterial heat balance. The teachings of calculating body temperature data is described in U.S. Pat. No. 6,292,685, which is hereby incorporated by reference. It is useful to note that embodiments of the present invention are not limited to temporal artery readings. Instead, any type of temperature detector may be used, including axillary, ear, or non-radiation detectors. Moreover, the medical device 220, instead of the temperature detector 210, may also calculate the temperature reading upon receiving the raw temperature data such as heat flux and ambient temperature data. One such example is shown in FIG. 1.
In particular, FIG. 1 illustrates the temporal arteries 12 and 14 that extend upwardly toward the side of the human face and bifurcate at 16 and 18 in the forehead region. In that region, the temporal artery passes over the skull bone very close to the skin and is thus termed the superficial temporal artery. The superficial temporal artery is, therefore, particularly accessible for providing temperature readings and, as an artery, has a temperature close to the heart temperature. Further, there are no known arterial/venus anastomoses, that is, shunts between the artery and veins for regulation of skin temperature. Accordingly, the blood flow is relatively stable, varying a maximum of only 50% as opposed to as much as 500% in other areas of the skin.
To locate the temporal artery, a temperature sensor, preferably a radiation detector 20, is scanned across the side of the forehead over the temporal artery while electronics in the detector search for the peak reading which indicates the temporal artery. Preferably, that temperature reading is then further processed in accordance with an algorithm specific to the temporal artery for providing a display temperature which may, for example, correspond to core, oral or rectal temperature.